package chapter3.test02;

public class TestCircle {
    public static void main(String[] args) {
        Circle c = new Circle();
        System.out.println(c.area(5));
    }
}
class Circle{
    double radius;
    public double area(double m){
        radius = m;
        double n = 3.1415926 * radius * radius;
        return n;
    }
}